This invention relates to a freight system and more particularly to an improved device for carrying articles between different locations and at different elevations.
A wide variety of conveyor mechanisms have been proposed for moving articles or work pieces between stations along a factory area. One form of conveyor mechanism includes a guide rail that describes the path along which the articles will be moved and a conveyor mechanism which cooperates with this guide rail for moving the articles from place to place. Quite frequently it is desirable that the elevations where the articles are moved and delivered may be at different locations. In order to accommodate this, the guide rail must have ascending and descending sections. Also, the conveyor mechanism should include an elevator or lift arrangement wherein the articles can be raised and lowered so that the work stations can be spaced at different heights from the guide rail. Conveyor systems of this general type are shown in the copending applications entitled "Freight System", Ser. No. 385,576 filed July 26, 1989 and Ser. No. 391,476, filed Aug. 9, 1989 and assigned to the assignee hereof.
In many instances, it is desirable that the article being transported is maintained in a horizontal position even though the conveyor mechanism is ascending or descending. This can be accomplished by having a differential type of elevator mechanism that operates so as to maintain the article in its horizontal position. However, such systems are quite complicated and further add to the complexity of the necessary controls.
It is, therefore, a principal object of this invention to provide an improved conveying apparatus for moving articles along a path at different levels and maintaining the article in a horizontal position even when ascending or descending.
It is a further object of this invention to provide a relatively simple conveyor mechanism wherein articles may be raised and lowered while they travel along a path and will be automatically and simply maintained in a horizontal position during such movement.